Dong Shuai, Yu Rong, Liu J-M, Dagotto Elbio
Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA.
Phys Rev Lett. 2009 Sep 4;103(10):107204. doi: 10.1103/PhysRevLett.103.107204. Epub 2009 Sep 3.
The phase diagram of quarter-hole-doped perovskite manganites is investigated using the double-exchange model. An exotic striped type-II multiferroic phase, where 25% of the nearest-neighbor spin couplings are orthogonal to each other, is found in the narrow-bandwidth region. Comparing with the spiral-spin ordering phase of undoped manganites, the multiferroic Curie temperature of the new phase is estimated to be approximately 4 times higher, while the ferroelectric polarization is similar in magnitude. Our study provides a path for noncollinear spin multiferroics based on electronic self-organization, different from the traditional approach based on superexchange frustration.
利用双交换模型研究了四分之一空穴掺杂钙钛矿锰氧化物的相图。在窄带宽区域发现了一种奇特的条纹型II类多铁性相，其中25%的最近邻自旋耦合相互正交。与未掺杂锰氧化物的螺旋自旋有序相相比，新相的多铁性居里温度估计高出约4倍，而铁电极化幅度相似。我们的研究为基于电子自组织的非共线自旋多铁性提供了一条途径，不同于基于超交换失配的传统方法。
